Variable ‘time_zone’ can’t be set to the value of ‘NULL’解决方法

MYSQL恢复数据库时出现如下错误：
ERROR 1231 (42000): Variable ‘time_zone’ can’t be set to the value of ‘NULL’
ERROR 1231 (42000): Variable ‘sql_mode’ can’t be set to the value of ‘NULL’
ERROR 1231 (42000): Variable ‘foreign_key_checks’ can’t be set to the value of ‘NULL’
ERROR 1231 (42000): Variable ‘unique_checks’ can’t be set to the value of ‘NULL’
ERROR 1231 (42000): Variable ‘character_set_client’ can’t be set to the value of ‘NULL’
Query OK, 0 rows affected (0.00 sec)

解决方式：

mysql> set global max_allowed_packet=1000000000;

mysql> source ./my_db.sql;